1. Field of Invention
This invention relates to a respiration system. In one of its aspects, the invention relates to a respiration system in which an inspiration sensitive ventilation system is rendered inoperative during a given time interval and operative thereafter for a single ventilation assist before weaning a patient from a respiration system.
2. State of the Prior Art
Respiration systems are well known and are in common use. An example of a respirator system is the MA-1 ventilator sold by Puritan-Bennett Corporation of Kansas City, Missouri. Respirator systems are also disclosed in many U.S. patents, including the U.S. patents to Bartels U.S. Pat. No. 3,664,361, Beasley U.S. Pat. No. 3,368,555, Beasley U.S. Pat. No. 3,395,669, and Weigl U.S. Pat. No. 3,817,246.
Respirators operate in basically two modes. In one mode, a ventilation assist is provided to a patient upon inhalation at every breath. In another mode, a ventilation assist is provided at timed intervals for the patient regardless of the point in the respiration cycle.
It has been found that patients become dependent on ventilation assist from a respiration system and prefer to rely on the respirator rather than the patients' own respiratory system. Recently, the timed interval mode of the respiration system has been used in an attempt to wean the patients from the respirator system. In this mode, a ventilation assist is provided to the patient after predetermined periods of time between which the patient must breathe on his own. Presently, the times provided in the machines do not have a long enough cycle times to permit complete weaning of the patients from the machine. Further, and perhaps more important, the use of a mandatory assist after a predetermined time is psychologically undesirable for the patient because the patient tends to be apprehensive as to when the mandatory assist will be supplied. Possibly, the mandatory assist would be provided at the exhilation stage of the patient's breathing cycle. Fortuitously, it may be applied during the inhalation stage. Even if applied during the inhalation stage, it may be at an inappropriate period in the patient's respiratory cycle.